(א) וַיֹּ֤אמֶר יי אֶל־מֹשֶׁ֣ה וְאֶֽל־אַהֲרֹ֔ן בְּאֶ֥רֶץ מִצְרַ֖יִם לֵאמֹֽר׃ (ב) הַחֹ֧דֶשׁ הַזֶּ֛ה לָכֶ֖ם רֹ֣אשׁ חֳדָשִׁ֑ים רִאשׁ֥וֹן הוּא֙ לָכֶ֔ם לְחָדְשֵׁ֖י הַשָּׁנָֽה׃
(1) The LORD said to Moses and Aaron in the land of Egypt: (2) This month shall mark for you the beginning of the months; it shall be the first of the months of the year for you.
(א) החדש הזה. א''ר יהודה הפרסי כי ישראל היו מונים כפי שנות החמה כמשפט העמים הערלים
This month - Rabbi Yehuda the Persian says that the Jewish people used to count according to solar years, like the nations of the world...
(א) החדש הזה. הֶרְאָהוּ לְבָנָה בְּחִדּוּשָׁהּ וְאָמַר לוֹ כְּשֶׁהַיָּרֵחַ מִתְחַדֵּשׁ יִהְיֶה לְךָ רֹאשׁ חֹדֶשׁ (מכילתא).
(1) החדש הזה — He showed him the moon in the first stage of its renewal, and He said to him, “The time when the moon renews itself thus, shall be unto you the beginning of the month”. (The translation therefore is: “This stage of renewal (חדש) shall be the moment of beginning the months”;
This is the moment when the Jews start to be their own people - when they start counting by the moon. Outside of simple counting time, what is symbolized by counting by the moon?
ב) החדש הזה. שם חדש יבא על חדשי הלבנה שהיא תתעלם ותתחדש, והחמה אין לה חדשים
Malbim - "this month" - the word chodesh refers to the months of the moon which disappears and then is renews. And the sun does not have months....
והנה אין ללבנה שנה כלל. כאשר אין לשמש חדש כלל. כי לא יתחדש בשמש דבר רק דבר החדוש הוא לאור הלבנה. ובעבור זה נקרא חדש.
Ibn Ezra:
... the moon doesn't have a year, just like the sun doesn't have a month. Because the sun does not have any renewal - the only thing that is renewed is the light of the moon. And therefore a month is called 'chodesh' (new).
Malbim - the moon disappears and renews -
There is one stage that is completely blank, and this is scary.
Ibn Ezra - The moon has renewal -
Moon = cycles. You never get a half-sun full sun.
And clearly the moon is associated with women and cycles.
Outside of the obvious, what cycles do you go through?
When the new cycle starts again, we celebrate.
עַל חֹדֶשׁ נִיסָן אָמַר לוֹ, זֶה יִהְיֶה רֹאשׁ לְסֵדֶר מִנְיַן הֶחֳדָשִׁים, שֶׁיְּהֵא אִיָּר קָרוּי שֵׁנִי, סִיוָן שְׁלִישִׁי:
He really spoke this in reference to the month Nisan: this month shall be the beginning in the order of counting the months, so that Iyar shall be called the second, Sivan the third.
Even though we are moon-month people, we also have a year, and it starts in Nissan.
Why Nissan? Leaving Egypt is the beginning of the Jewish people
It is also the beginning of the holiday year.
Right now we are on the first day of Shevat. That's the 11th month - so, two months before Nissan. (10 weeks until Pesach) If Nissan is the beginning of the year, what is Shevat?
The sap is rising! We're getting ready for renewal. We're starting to get activated.